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SelectedWorks

1997

Cardiovascular Health Study (CHS)

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Full-Text Articles in Physical Sciences and Mathematics

Effect Size And Power For Clinical Trials Using Years Of Healthy Life As The Primary Endpoint, Paula Diehr Jun 1997

Effect Size And Power For Clinical Trials Using Years Of Healthy Life As The Primary Endpoint, Paula Diehr

Paula Diehr

Some clinical trials perform repeated measurements on patients over time, plot those measures against time, and summarize the results in terms of the area under the curve. If the measured variable is health status, the summary outcome is sometimes referred to as years of healthy life (YHL), or quality-adjusted life years (QALY). This paper investigates some theoretical and practical aspects of randomized trials designed to assess measures such as YHL. We first derived algebraic expressions for the effect size of YHL measures under several theoretical models of the treatment's effect on health. We used these expressions to examine how the …